USPTO Patents Application 09993647

WORLD INTELLECTUAL PROPERTY ORGANIZATION
International Bureau

PCT

INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)

(51) International Patent Classification 6 :

C07C 275/42, 311/39, 311/51, 335/22,
275/40, 311/08, 311/60, 271/58, A61K
31/19, 31/17, 31/18

Al

(11) International Publication Number: WO 97/45400

(43) International Publication Date: 4 December 3997 (04.12.97)

(21) International Application Number: PCT/EP97/02723

(22) International Filing Date: 26 May 1997 (26.05.97)

(30) Priority Data:

0602/96
0452/97

24 May 1996 (24.05.96) DK
22 April 1997 (22.04.97) DK

(71) Applicant (for all designated States except US): NEU-

ROSEARCH A/S [DK/DK]; Smedeland 26B, DK-2600
Glostrup (DK).

(72) Inventors; and

(75) Inventors/Applicants (for US only): CHRISTOPHERSEN,
Palle [DK/DK]; Axel Juels A116 48, DK-2750 Ballerup
(DK). PEDERSEN, Ove [DK/DK]; Tvindelstrupvej 38, DK-
4100 Ringsted (DK).

(74) Agent: GRUNECKER, KINKELDEY, STOCKMAIR &
SCHWANHAUSSER; Maximilianstrasse 58, D-80538
Munchen (DE).

(81) Designated States: AL, AM, AT, AU, AZ, BA, BB, BG, BR,
BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE,
GH, HU, IL, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR,
LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ,
PL, PT, RO, RU, SD, SE, SG, SI, SK, TJ, TM, TR, TT,
UA, UG, US, UZ, VN, YU, ARIPO patent (GH, KE, LS,
MW, SD, SZ, UG), Eurasian patent (AM, AZ, BY, KG, KZ,
MD, RU, TJ, TM), European patent (AT, BE, CH, DE, DK,
ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE), OAPI
patent (BF, BJ, CF, CG, CI, CM, GA, GN, ML, MR, NE,
SN, TD, TG).

Published

With international search report.

(54) Title: PHENYL DERIVATIVES CONTAINING AN ACIDIC GROUP, THEIR PREPARATION AND THEIR USE AS CHLORIDE
CHANNEL BLOCKERS

R" ^ / x y- z - ( \ R 3 CO

(57) Abstract

The present patent application relates to compounds, having formula (I) or a pharmaceutical^ acceptable salt thereof wherein one of
R , R and R is a non-cyclic acidic group having a pKa value below 8 or a group which is in vivo convertible to such a group; R 4 R 5 and
the other two of the substituents R 1 , R 2 and R 3 are each independently selected from hydrogen, alkyl, cycloalkyl, cydoalkylalkyl, alkenyl,
alkynyl, alkoxy, hydroxy, halogen, trifluoromethyl, trifiuoromethoxy, cyano, nitro, amino, and aryl, aralkyl, arylamino, aryloxy, aryl-CO-]
or heteroaryl, wherein the aryl and heteroaryl groups may be substituted one or more times with substituents selected from alkyl, cycloalkyl,'
cydoalkylalkyl, alkenyl, alkynyl, hydroxy, alkoxy, halogen, trifluoromethyl, trifiuoromethoxy, cyano, nitro and amino; or R 3 and R 4 or R 4
and R5 together form a fused 4- to 7-membered carbocyclic ring which may be unsaturated, or partially or fully saturated, while the other
substituents R>, R 2 , R3, R 4 and R* are as defined above; Y is -CO-, -CS-, -SO2-, or -C(-N-RS)-, wherein R 8 is hydrogen, alkyl, or cyano;
u % i ; CH2 NH -' or -SO2-NH-; Z is NR«, O, -CH-CH-, -C-C-, -N-CH-, or -CH-N-; wherein R« is hydrogen, or alkyl; R 1 ', R> 2 , R'3,
and R 5 are each independently selected from hydrogen, alkyl, cycloalkyl, cydoalkylalkyl, alkenyl, alkynyl, alkoxy, hydroxy halogen
trifluoromethyl, trifiuoromethoxy, cyano, nitro, amino, -NHSO2-R 7 , -COOR 7 , -S0 2 N(R 7 ) 2 , -S0 2 OR 7 and -COR 7 , wherein R 7 is hydrogen
alkyl, cycloalkyl, cydoalkylalkyl, alkenyl, alkynyl, aryl or aralkyl; and aryl, aralkyl, arylamino, aryloxy, aryl-CO-, or heteroaryl, wherein
the aryl and heteroaryl groups may be substituted one or more times with substituents selected from alkyl, cycloalkyl cydoalkylalkyl
o n 6ny n alkyny !i h y drox y. alkoxy, halogen, trifluoromethyl, trifiuoromethoxy, cyano, nitro and amino; or one of R 11 and R 12 , R 12 and
R » R and Ri" or R 14 and R'» together form a fused 4- to 7-membered carbocyclic ring which may be unsaturated, or partially or fully
saturated, while the other substituents R", R'2, R'3, R 14 and R i5 are as defined above ^ COItlpounds are uscfu] for , he treatment of
diseases and disorders responsive to the blockage of chloride channels.

FOR THE PURPOSES OF INFORMATION ONLY

Codes used to identify States party to the PCT on the front pages of pamphlets publishing international applications under the PCT.

AL

Albania

ES

Spain

LS

I^esotho

SI

Slovenia

AM

Armenia

FI

Finland

LT

Lithuania

SK

Slovakia

AT

Austria

FR

France

LU

Luxembourg

SN

Senegal

AU

Australia

GA

Gabon

LV

Latvia

sz

Swaziland

AZ

Azerbaijan

GB

United Kingdom

MC

Monaco

TD

Chad

BA

Bosnia and Herzegovina

GE

Georgia

MD

Republic of Moldova

TG

Togo

BB

Barbados

GH

Ghana

MG

Madagascar

TJ

Tajikistan

BE

Belgium

GN

Guinea

MK

The former Yugoslav

TM

Turkmenistan

BF

Burkina Faso

GR

Greece

Republic of Macedonia

TR

Turkey

BG

Bulgaria

HU

Hungary

ML

Mali

TT

Trinidad and Tobago

BJ

Benin

IE

Ireland

MN

Mongolia

UA

Ukraine

BR

Brazil

IL

Israel

MR

Mauritania

UG

Uganda

BY

Belarus

IS

Iceland

MW

Malawi

US

United States of America

CA

Canada

IT

Italy

MX

Mexico

uz

Uzbekistan

CF

Central African Republic

JP

Japan

NE

Niger

VN

Viet Nam

CG

Congo

KE

Kenya

NL

Netherlands

YU

Yugoslavia

CH

Switzerland

KG

Kyrgyzstan

NO

Norway

zw

Zimbabwe

CI

COte d'lvoire

KP

Democratic People's

NZ

New Zealand

CM

Cameroon

Republic of Korea

PL

Poland

CN

China

KR

Republic of Korea

PT

Portugal

cu

Cuba

KZ

Kazakstan

RO

Romania

cz

Czech Republic

LC

Saint Lucia

RU

Russian Federation

DE

Germany

LI

Liechtenstein

SD

Sudan

DK

Denmark

LK

Sri Lanka

SE

Sweden

EE

Estonia

LR

Liberia

SG

Singapore

WO 97/45400

PCT/EP97/02723

. P .c£ N a^™ «™. ATIVES CONTAIN lNG AN ACIDIC GROUP, THEIR PREPARATION AND THEIR
USE AS CHLORIDE CHANNEL BLOCKERS

The present invention relates to phenyl derivatives which are valuable blockers of
chloride channels and as such useful for the treatment of sickle cell anaemia, brain
oedema following ischaemia or tumours, diahreea, hypertension (diuretic) and for the
reduction of the intraocular pressure for the treatment of disorders such as glaucoma.
The compounds of the invention may also be useful in the treatment of allergic or
inflammatory conditions and for the promotion of wound healing.

Background

Chloride channels serve a wide variety of specific cellular functions and contribute to
the normal function of skeletal and smooth muscle cells. Blockers of chloride channels
are known to be useful in the treatment of brain oedema following ischaemia or
tumours, diahreea, hypertension (diuretic) and for the reduction of the intraocular
pressure in disorders such as glaucoma.

Sickle cell anaemia and the existence of sickle haemoglobin was the first genetic
disease to be understood at the molecular level. The genetic defect underlying sickle
cell anaemia causes the substitution of a single amino acid resulting in a mutant
haemoglobin, sickle haemoglobin.

The physical manifestations of sickle cell disease is anaemia and painful ischaemic
crises due to occlusion of the microcirculation by deformed erythrocytes (sickle cells).
The primary cause of sickle erythrocyte deformation and distortion (or sickling) is a
reversible polymerisation and gelation of sickle haemoglobin induced at the low oxygen
tensions prevalent in metabolically active tissues. Sickle cells are also characterised
by an enhanced cation permeability, resulting in cation depletion and cellular
dehydration. Since the delay time for the polymerisation has been described as an
extremely steep function of the sickle haemoglobin concentration itself, any decrease
in cell volume will greatly increase the probability of sickling and thereby of vessel
occlusion. Compounds which blocks the deoxygenation induced salt and volume
(water) loss may delay the sickling process enough to avoid occlusion upon the
passage of the sickle erythrocyte through metabolically active tissue. It has been
estimated that a delay time of only 10 sec may suffice.

WO 97/45400

2

PCT/EP97/02723

Several membrane ion channels and transporters present in normal erythrocytes has
been suggested to participate in the altered membrane permeabilities of sickle cells.
The favoured hypothesis has been stimulation of the Ca 2+ -activated K^-channel and
several blockers of this channel has been suggested as therapeutic agents for the
treatment of sickle-cell anaemia ( Effects of Cetiedil on Monovalent Cation
Permeability in the Erythrocyte: An explanation for the Efficacy of Cetiedil in the
treatment of Sickle Cell Anaemia, Berkowitz, L. R., Orringer, E. P., Blood cells, (283-
288 (1982) and US patent No. 5.273.992).

Since, K + efflux through a K-channel must be followed by an equal efflux of CI" to
maintain electroneutrality, blockade of erythrocyte chloride channels are predicted to
be as effective as blocking the K-channels itself. An advantage to the use of chloride
channel blockers is that salt loss which may occur due to activation of unknown
K-channel types will indirectly be blocked too.

The compounds of the present invention are valuable blockers of chloride channels as
determined by concomitant measurements of conductive netfluxes of chloride and
membrane potentials in suspensions of erythrocytes, and the compounds are therefore
predicted to be useful for the treatment of ailments responsive to the blockade of
chloride channels, including sickle cell anaemia.

The use of blockers of chloride channels for the treatment of sickle-cell anaemia form
a new therapeutic approach.

Several chloride channel blockers and the use thereof have already been described in
the technical literature:

Pfliigers Arch (1986), 407 (suppl. 2), pages 128-141 describe several compounds with
chloride channel blocking activity. A very potent compound described herein is
5-nitro-2-(3-phenylpropylamino)benzoic acid. The reference do not disclose the use of
chloride channel blockers for the treatment of sickle cell anaemia.

US patent No. 4.889.612 describes Calixarene derivatives and their use as chloride
channel blockers.

WO 97/45400

3

PCT7EP97/02723

US patent No. 4.994.493 describes certain 5-nitrobenzoic acid derivatives and their
use in the treatment of cerebral oedema.

WO 96/16647 describes the use of chloride channel blockers for the reduction of the
intraocular pressure and specifically the use of chloride channel blockers for the
treatment of glaucoma.

It is an object of the present invention to provide a series of phenyl derivatives carrying
an acidic group and pharmaceutical^ acceptable salts thereof which are useful in the
treatment of disorders or diseases responsive to the blockade of chloride channels.

Still another object of the present invention is to provide a method of treating disorders
or diseases responsive to the blockade of chloride channels, such as for example brain
oedema following ischaemia or tumours, diahreea, hypertension (diuretic), glaucoma
and in particular sickle-cell anaemia. A further object of the present invention is to
provide a method for the treatment of allergic or inflammatory conditions and for the
promotion of wound healing.

Objects of the Invention

Summary of the Invention

The invention then comprises, inter alia, alone or in combination:

A compound having the formula

or a pharmaceutical^ acceptable salt thereof

wherein

one of R\ R 2 and R 3 is a non-cyclic acidic group having a pKa value below 8 or
a group which is in vivo convertible to such a group;

WO 97/45400

4

PCT/EP97/02723

R 4 , R 5 and the other two of the substituents R 1 , R 2 and R 3 are each independently
selected from hydrogen; alkyl; cycloalkyl; cycloalkylalkyl; alkenyl; alkynyl; alkoxy;
hydroxy; halogen; trifluoromethyl; trifluoromethoxy; cyano; nitro; amino; and aryl, aralkyl,
arylamino, aryloxy, aryl-CO-, or heteroaryl, wherein the aryl and heteroaryl groups may
be substituted one or more times with substituents selected from alkyl, cycloalkyl,
cycloalkylalkyl, alkenyl, alkynyl, hydroxy, alkoxy, halogen, trifluoromethyl,
trifluoromethoxy, cyano, nitro and amino; or R 3 and R 4 or R 4 and R 5 together form a
fused 4 to 7 membered carboxyclic ring which may be unsaturated, or partially or fully
saturated, while the other substituents R 1 , R 2 , R 3 , R 4 and R 5 is as defined above;

Y is -CO-, -CS-, -S0 2 -, or -C(=N-R 8 )-, wherein R 8 is hydrogen, alkyl, or cyano;

X is -NH-, -CH 2 -NH-, or -S0 2 -NH-;

Z is NR 6 , O, -CH=CH-, -C=C-, -N=CH-, or -CH=N-; wherein R 6 is hydrogen, or alkyl;

R 11 , R 12 , R 13 , R 14 and R 15 are each independently selected from hydrogen; alkyl;
cycloalkyl; cycloalkylalkyl; alkenyl; alkynyl; alkoxy; hydroxy; halogen; trifluoromethyl;
trifluoromethoxy; cyano; nitro; amino; -NHSO2-R 7 , -COOR 7 , -S0 2 N(R 7 ) 2 , -S0 2 OR 7 and
-CO-R 7 , wherein R 7 is hydrogen, alkyl, cycloalkyl, cycloalkylalkyl, alkenyl, alkynyl, aryl or
aralkyl; and aryl, aralkyl, arylamino, aryloxy, aryl-CO-, or heteroaryl, wherein the aryl and
heteroaryl groups may be substituted one or more times with substituents selected from
alkyl, cycloalkyl; cycloalkylalkyl; alkenyl; alkynyl; hydroxy, alkoxy, halogen,
trifluoromethyl, trifluoromethoxy, cyano, nitro and amino; or one of R 11 and R 12 , R 12 and
R 13 , R 13 and R 14 or R 14 and R 15 together form a fused 4 to 7 membered carboxyclic ring
which may be unsaturated, or partially or fully saturated, while the other substituents R 11 ,
R 12 , R 13 , R 14 and R 15 is as defined above;

a compound as above wherein one of R 1 , R 2 and R 3 is NH 2 ,
-COOR 9 , -CH 2 COOR 9 , -CONH 2 , -NHS0 2 -R 9 , -S0 2 N(R 9 ) 2 , -S0 2 OR 9 , -PO a H 2 .
-P0 3 RH, -P0 2 NH 2 , -CONHOH, -CONHCN, -CONH 2 S0 2 R 9 and -CONHNH 2 , wherein R 9
is hydrogen, alkyl, cycloalkyl, cycloalkylalkyl, alkenyl, alkynyl, aryl or aralkyl, and the
other of R 1 , R 2 and R 3 is as defined above;

WO 97/45400

PCT7EP97/02723

5

a pharmaceutical composition comprising a therapeutically effective amount of a
compound as above or a pharmaceutically acceptable salt thereof together with at
least one pharmaceutically acceptable carrier or diluent;

the use of a compound as above for the preparation of a medicament for the treatment
of a disorder or disease of a living animal body, including a human, which disorder or
disease is responsive to the blockade of chloride channels;

the use of a compound as above for the preparation of a medicament for the treatment
of sickle-cell anaemia, brain oedema following ischaemia, or tumours, diahreea,
hypertension (diuretic), glaucoma, allergic or inflammatory conditions and ulcers;

a method for the treatment of a disorder or disease of a living animal body, including a
human, which disorder or disease is responsive to the blockade of chloride channels,
comprising administering to a living animal body in need thereof a therapeutically
effective amount of a compound as above;

a method for the treatment of a disorder or disease of a living animal body which
disorder or disease is sickle-cell anaemia, brain oedema following ischaemia, or
tumours, diahreea, hypertension (diuretic), glaucoma, allergic or inflammatory
conditions and ulcers comprising administering to such a living animal body, including
a human, in need thereof a therapeutically effective amount of a compound as above;

a method for the preparation of a compound as above, comprising:

a) reacting a compound having the formula

R

12

R

11

wherein W is O, or S and R 11 , R 12 , R 13 , R 14 and R 15 is as defined above, with a
compound having the formula

WO 97/45400

6

PCT/EP97/02723

NHR

wherein R 1 , R 2 ,R 3 , R 4 , R 5 and R 6 is as defined above, or

b)

reacting a compound having the formula

R

R

R

15

11

X Y — NHR

,6

wherein X, Y, R 6 , R 11 , R 12 , R 13 , R 14 and R 15 is as defined above, with a compound
having the formula

wherein Hal is halogen and R 1 , R 2 , R 3 , R 4 and R 5 is as defined above,

whereafter the compound obtained is optionally converted to another compound of the
invention and/or a pharmaceutical^ acceptable salt thereof is formed using
conventional methods; and

the use of blockers of chloride channels of erythrocytes for the treatment of sickle cell
anaemia.

WO 97/45400

7

PCT/EP97/02723

Examples of pharmaceutical^ acceptable addition salts include inorganic and organic
acid addition salts such as the hydrochloride, hydrobromide, phosphate, nitrate,
perchlorate, sulfate, citrate, lactate, tartrate, maleate, fumarate, mandelate, benzoate,
ascorbate, cinnamate, benzenesulfonate, methanesulfonate, stearate, succinate,
glutamate, glycollate, toluene-p-sulphonate, formate, malonate, naphthalene-2-
sulphonate, salicylate and the acetate. Such salts are formed by procedures well
known in the art.

Other acids such as oxalic acid, while not in themselves pharmaceutical^ acceptable,
may be useful in the preparation of salts useful as intermediates in obtaining
compounds of the invention and their pharmaceutical^ acceptable acid addition salts.

Halogen is fluorine, chlorine, bromine or iodine.

Alkyl means a straight chain or branched chain of one to six carbon atoms, including
but not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, and
hexyl; methyl, ethyl, propyl and isopropyl are preferred groups.

Cycloalkyl means cyclic alkyl of three to seven carbon atoms, including but not limited
to cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl;

Cycloalkylalkyl means cycloalkyl as above and alkyl as above, meaning for example,
cyclop ropyl methyl .

Alkenyl means a group of from two to six carbon atoms, including at least one double
bond, for example, but not limited to ethenyl, 1,2- or 2,3-propenyl, 1 ,2-, 2,3-, or 3,4-
butenyl.

Alkynyl means a group of from two to six carbon atoms, including at least one triple
bond, for example, but not limited to ethynyl, 1 ,2-, 2,3-propynyl, 1 ,2-,2,3- or 3,4-
butynyl.

Alkoxy is O-alkyl, wherein alkyl is as defined above.

Amino is NH 2 or NH-alkyl or N-(alkyl) 2 , wherein alkyl is as defined above.

WO 97/45400

8

PCTYEP97/02723

A non-cyclic acidic group having a pKa below 8 or a group which is in vivo convertible
to such group include groups such as NH 2 , -COOR 9 , -CH 2 COOR 9 , -CONH 2 ,
-NHS0 2 -R 9 , -S0 2 N(R 9 ) 2 , -S0 2 OR 9 , -P0 3 H 2 , -P0 3 RH, -P0 2 NH 2l -CONHOH, -CONHCN,
-CONH 2 S0 2 R 9 and -CONHNH 2) wherein R 9 is hydrogen, alkyl, cycloalkyl,
cycloalkylalkyl, alkenyl, alkynyl, aryl or aralkyl.

Heteroaryl is a 5- or 6-membered heterocyclic monocyclic group. Such a monocyclic
heteroaryl group includes, for example, oxazol-2-yl, oxazol-4-yl, oxazol-5-yl, isoxazol-3-
yl, isoxazol-4-yl, isoxazol-5-yl, thiazol-2-yl, thiazol-4-yl, thiazol-5-yl, isothiazol-3-yl,
isothiazol-4-yl, isothiazol-5-yl, 1 ,2,4-oxadiazol-3-yl, 1,2,4-oxadiazol-5-yl, 1,2,4-
thiadiazol-3-yl, 1,2,4-thiadiazol-5-yl, 1 ,2,5-oxadiazol-3-yl, 1 ,2,5-oxadiazol-4-yl, 1,2,5-
thiadiazol-3-yl, 1,2,5-thiadiazol-4-yl, 1-imidazolyl, 2-imidazolyl, 4-imidazolyl, 1-pyrrolyl,
2-pyrrolyl, 3-pyrrolyl, 2-furanyl, 3-furanyl, 2-thienyl, 3-thienyl, 2-pyridyl, 3-pyridyl, 4-
pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 3-pyridazinyl, 4-pyridazinyl, 2-
pyrazinyl, 1-pyrazolyl, 3-pyrazolyl, and 4-pyrazolyl.

Aryl means an aromatic group such as phenyl or naphtyl.

Aralkyl means arylalkyl wherein alkyl and aryl is as defined above, meaning for
example benzyl, or phenethyl.

I. p. means intraperetoneally, which is a well known route of administration.

P.o. means peroral, which is a well known route of administration.

Further, the compounds of this invention may exist in unsolvated as well as in solvated
forms with pharmaceuticaily acceptable solvents such as water, ethanol and the like. In
general, the solvated forms are considered equivalent to the unsolvated forms for the
purposes of this invention.

It will be appreciated by those skilled in the art that the compounds of the present
invention contain several chiral centres and that such compounds exist in the form of
isomers (i.e. enantiomers). The invention includes all such isomers and any mixtures
thereof including racemic mixtures.

WO 97/45400

9

PCT7EP97/02723

Some of the compounds of the present invention exist in (+) and (-) forms as well as in
racemic forms. Racemic forms can be resolved into the optical antipodes by known
methods, for example, by separation of diastereomeric salts thereof with an optically
active acid, and liberating the optically active amine compound by treatment with a
base. Another method for resolving racemates into the optical antipodes is based upon
chromatography on an optically active matrix. Racemic compounds of the present
invention can thus be resolved into their optical antipodes, e.g., by fractional
crystallization of d- or I- (tartrates, mandelates, or camphorsulphonate) salts for
example. The compounds of the present invention may also be resolved by the
formation of diastereomeric amides by reaction of the compounds of the present
invention with an optically active activated carboxylic acid such as that derived from (+)
or (-) phenylalanine, (+) or (-) phenylglycine, (+) or (-) camphanic acid or by the
formation of diastereomeric carbamates by reaction of the compounds of the present
invention with an optically active chloroformate or the like.

Additional methods for the resolvation of optical isomers, known to those skilled in the
art may be used, and will be apparent to the average worker skilled in the art. Such
methods include those discussed by J. Jaques, A. Collet, and S. Wilen in
"Enantiomers, Racemates, and Resolutions", John Wiley and Sons, New York (1981).

The compounds of the invention may be prepared in numerous ways. The compounds
of the invention and their pharmaceutical^ acceptable derivatives may thus be
prepared by any method known in the art for the preparation of compounds of
analogous structure, and as shown in the representative examples which follow.

Biology

The compounds of the present invention are potent blockers of chloride channels in
normal as well as sickle cell erythrocytes. The ability of the compounds to block the
erythrocyte chloride channels could not be demonstrated by classical
electrophysiological measurements such as patch clamping, since the channel unit
conductance is below the detection limit of these techniques.

WO 97/45400

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PCT/EP97/02723

All dose-response experiments were therefore performed by concomitant
measurements of conductive netfluxes of CI (J C( ) and membrane potentials (V m ) in
suspensions of erythrocytes (Bennekou, P. and Christophersen, P. (1986), Flux ratio
of Valinomycin - Mediated K + Fluxes across the Human Red Cell Membrane in the
presence of the Protronophore CCCP. J. Membrane Biol. 93, 221-227. ). The
membrane CI -conductances were calculated by the following equation (Hodgkin, A. L.
and Huxley, A.F. (1952) The components of membrane conductance in the giant axon
of loligo. J. Physiol. Lond. 116, 449-472):

F*J C i

Gci =

(V m - Eci)

where F is the Faraday constant and E a is the Nernst potential for the Cl-ion.
Administration of N-(3-Trifluoromethylphenyl)-N'-(2-carboxyphenyl) urea to a
suspension of normal erythrocytes blocked G C i more than 95 % with an IC 50 -value of
0.6 u.M. The compound equipotently blocked G C i from oxygenated as well as
deoxygenated homozygoteous sickle cell erythrocytes.

Experimentally induced cell volume losses were measured as changes in the relative
volume of packed cells. Inducing a massive water and salt loss (KCl) by addition the
K + -ionophore valinomycin to the suspension for 5 min reduced the cell volume by 26
%. N-(3-Trifluoromethylphenyl)-N'-(2-carboxyphenyl) urea dose-dependently (!C 50 -
value of 1 .2 nM) reduced the volume loss to 7 %.

Deoxygenation induced permeability increases of sickle cells were estimated by
measuring the extracellular K + -concentration vs time. Normal erythrocytes exhibited
very smalt K + -f luxes, which was insensitive to deoxygenation and insensitive to 10 fiM
N-(3-Trifluoromethylphenyl)-N'-(2-carboxyphenyl) urea. The K + flux from oxygenated
sickle erythrocytes was 2-3 times higher than from normal erythrocytes and these
fluxes was accelerated 4 - 8 times upon deoxygenation. In presence of
N-(3-Trifluoromethylphenyl)-N'-(2-carboxyphenyl) urea (10 jxM) the basal KMlux from
sickle erythrocytes was normalised and the deoxygenation induced flux component
were nearly abolished.

WO 97/45400

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PCT/EP97/02723

N-(3-Trifluoromethyiphenyl)-N'-(2-carboxyphenyl) urea was non-toxic to mice at
concentrations up to 150 mg/kg i.p. and i.v.

Pharmaceutical compositions

While it is possible that, for use in therapy, a compound of the invention may be
administered as the raw chemical, it is preferable to present the active ingredient as a
pharmaceutical formulation.

The invention thus further provides pharmaceutical formulations comprising a
compound of the invention or a pharmaceutical ly acceptable salt or derivative thereof
together with one or more pharmaceutically acceptable carriers therefor and,
optionally, other therapeutic and/or prophylactic ingredients. The carrier(s) must be
"acceptable" in the sense of being compatible with the other ingredients of the
formulation and not deleterious to the recipient thereof.

Pharmaceutical formulations include those suitable for oral, rectal, nasal, topical
(including buccal and sub-lingual), vaginal or parenteral (including intramuscular, sub-
cutaneous and intravenous) administration or in a form suitable for administration by
inhalation or insufflation.

The compounds of the invention, together with a conventional adjuvant, carrier, or
diluent, may thus be placed into the form of pharmaceutical compositions and unit
dosages thereof, and in such form may be employed as solids, such as tablets or filled
capsules, or liquids such as solutions, suspensions, emulsions, elixirs, or capsules
filled with the same, all for oral use, in the form of suppositories for rectal
administration; or in the form of sterile injectable solutions for parenteral (including
subcutaneous) use. Such pharmaceutical compositions and unit dosage forms thereof
may comprise conventional ingredients in conventional proportions, with or without
additional active compounds or principles, and such unit dosage forms may contain
any suitable effective amount of the active ingredient commensurate with the intended
daily dosage range to be employed. Formulations containing ten (10) milligrams of
active ingredient or, more broadly, 0.1 to one hundred (100) milligrams, per tablet, are
accordingly suitable representative unit dosage forms.

WO 97/45400

12

PCT/EP97/02723

The compounds of the present invention can be administrated in a wide variety of oral
and parenteral dosage forms. It will be obvious to those skilled in the art that the
following dosage forms may comprise, as the active component, either a compound of
the invention or a pharmaceutical^ acceptable salt of a compound of the invention.

For preparing pharmaceutical compositions from the compounds of the present
invention, pharmaceutically acceptable carriers can be either solid or liquid. Solid form
preparations include powders, tablets, pills, capsules, cachets, suppositories, and
dispersible granules. A solid carrier can be one or more substances which may also
act as diluents, flavouring agents, solubilizers, lubricants, suspending agents, binders,
preservatives, tablet disintegrating agents, or an encapsulating material.

In powders, the carrier is a finely divided solid which is in a mixture with the finely
divided active component.

In tablets, the active component is mixed with the carrier having the necessary binding
capacity in suitable proportions and compacted in the shape and size desired.

The powders and tablets preferably contain from five or ten to about seventy percent
of the active compound. Suitable carriers are magnesium carbonate, magnesium
stearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin, tragacanth,
methylcellulose, sodium carboxymethylcellulose, a low melting wax, cocoa butter, and
the like. The term "preparation" is intended to include the formulation of the active
compound with encapsulating material as carrier providing a capsule in which the
active component, with or without carriers, is surrounded by a carrier, which is thus in
association with it. Similarly, cachets and lozenges are included. Tablets, powders,
capsules, pills, cachets, and lozenges can be used as solid forms suitable for oral
administration.

For preparing suppositories, a low melting wax, such as admixture of fatty acid
glycerides or cocoa butter, is first melted and the active component is dispersed
homogeneously therein, as by stirring. The molten homogenous mixture is then poured
into convenient sized molds, allowed to cool, and thereby to solidify.

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PCT/EP97/02723

Formulations suitable for vaginal administration may be presented as pessaries,
tampons, creams, gels, pastes, foams or sprays containing in addition to the active
ingredient such carriers as are known in the art to be appropriate.

Liquid form preparations include solutions, suspensions, and emulsions, for example,
water or water-propylene glycol solutions. For example, parenteral injection liquid
preparations can be formulated as solutions in aqueous polyethylene glycol solution.

The compounds according to the present invention may thus be formulated for
parenteral administration (e.g. by injection, for example bolus injection or continuous
infusion) and may be presented in unit dose form in ampoules, pre-filled syringes,
small volume infusion or in multi-dose containers with an added preservative. The
compositions may take such forms as suspensions, solutions, or emulsions in oily or
aqueous vehicles, and may contain formulatory agents such as suspending, stabilising
and/or dispersing agents. Alternatively, the active ingredient may be in powder form,
obtained by aseptic isolation of sterile solid or by lyophilisation from solution, for
constitution with a suitable vehicle, e.g. sterile, pyrogen-free water, before use.

Aqueous solutions suitable for oral use can be prepared by dissolving the active
component in water and adding suitable colorants, flavours, stabilizing and thickening
agents, as desired.

Aqueous suspensions suitable for oral use can be made by dispersing the finely
divided active component in water with viscous material, such as natural or synthetic
gums, resins, methylcellulose, sodium carboxymethylcellulose, or other well known
suspending agents.

Also included are solid form preparations which are intended to be converted, shortly
before use, to liquid form preparations for oral administration. Such liquid forms include
solutions, suspensions, and emulsions. These preparations may contain, in addition to
the active component, colorants, flavours, stabilizers, buffers, artificial and natural
sweeteners, dispersants, thickeners, solubilizing agents, and the like.

For topical administration to the epidermis the compounds according to the invention
may be formulated as ointments, creams or lotions, or as a transdermal patch.

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Ointments and creams may, for example, be formulated with an aqueous or oily base
with the addition of suitable thickening and/or gelling agents. Lotions may be
formulated with an aqueous or oily base and will in general also contain one or more
emulsifying agents, stabilising agents, dispersing agents, suspending agents,
thickening agents, or colouring agents.

Formulations suitable for topical administration in the mouth include lozenges
comprising active agent in a flavoured base, usually sucrose and acacia or tragacanth;
pastilles comprising the active ingredient in an inert base such as gelatin and glycerin
or sucrose and acacia; and mouthwashes comprising the active ingredient in a suitable
liquid carrier.

Solutions or suspensions are applied directly to the nasal cavity by conventional
means, for example with a dropper, pipette or spray. The formulations may be
provided in single or multidose form. In the latter case of a dropper or pipette, this may
be achieved by the patient administering an appropriate, predetermined volume of the
solution or suspension. In the case of a spray, this may be achieved for example by
means of a metering atomising spray pump.

Administration to the respiratory tract may also be achieved by means of an aerosol
formulation in which the active ingredient is provided in a pressurised pack with a
suitable propellant such as a chlorofluorocarbon (CFC) for example
dichlorodifluoromethane, trichlorofluoromethane, or dichlorotetrafluoroethane, carbon
dioxide, or other suitable gas. The aerosol may conveniently also contain a surfactant
such as lecithin. The dose of drug may be controlled by provision of a metered valve.

Alternatively the active ingredients may be provided in the form of a dry powder, for
example a powder mix of the compound in a suitable powder base such as lactose,
starch, starch derivatives such as hydroxypropylmethyl cellulose and
polyvinylpyrrolidone (PVP). Conveniently the powder carrier will form a gel in the nasal
cavity. The powder composition may be presented in unit dose form for example in
capsules or cartridges of, e.g., gelatin, or blister packs from which the powder may be
administered by means of an inhaler.

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In formulations intended for administration to the respiratory tract, including intranasal
formulations, the compound will generally have a small particle size for example of the
order of 5 microns or less. Such a particle size may be obtained by means known in
the art, for example by micronization.

When desired, formulations adapted to give sustained release of the active ingredient
may be employed.

The pharmaceutical preparations are preferably in unit dosage forms. In such form, the
preparation is subdivided into unit doses containing appropriate quantities of the active
component. The unit dosage form can be a packaged preparation, the package
containing discrete quantities of preparation, such as packeted tablets, capsules, and
powders in vials or ampoules. Also, the unit dosage form can be a capsule, tablet,
cachet, or lozenge itself, or it can be the appropriate number of any of these in
packaged form.

Tablets or capsules for oral administration and liquids for intravenous administration
are preferred compositions.

Methods of treating

The compounds of the present invention are, due to their potent chloride channel
blocking activity, useful in the treatment of sickle cell anaemia, brain oedema following
ischaemia or tumors, diahreea, and hypertension (diuretic) as well as other disorders
responsive to the blockade of chloride channels. The compounds of the invention may
also be useful in the treatment of allergic and inflammatory conditions, for the
promotion of wound healing or the treatment of ulcers. The compounds of this
invention may accordingly be administered to a living animal body, including a human,
in need of treatment, alleviation, or elimination of an indication associated with or
responsive to chloride channel blocking activity. This includes especially sickle cell
anaemia, brain oedema following ischaemia or tumors, diahreea, and hypertension
(diuretic).

Suitable dosage range are 0.1-500 milligrams daily, and especially 10-70 milligrams
daily, administered once or twice a day, dependent as usual upon the exact mode of
administration, form in which administered, the indication toward which the
administration is directed, the subject involved and the body weight of the subject

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involved, and further the preference and experience of the physician or veterinarian in
charge.

The following examples will illustrate the invention further, however, they are not to be
construed as limiting.

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Example 1

3'-Trifluoromethylphenyl-2-carboxyphenyl urea

3'-Triflouromethylphenyl isocyanate (1.87g, 10 mmol) and 2-aminobenzoic acid (1.37g,
10 mmol) were in toluene (50 mL) until the 2-aminobenzoic acid had been consumed.
After cooling to room temperature the product was filtered off. M.p. 171-172 °C.

The following compounds were prepared analogously:

3'-Trifluoromethylphenyl-3-carboxyphenyl urea. M.p. 183-185 °C.
2'-Methoxy-5'-chlorophenyl-3-carboxyphenyl urea.
3'-Trifiuoromethylphenyl-2-carboxy-5-nitrophenyl urea. M.p. 206-207 °C.
3'-Trifluoromethylphenyl-5-chloro-2-nitrophenyl urea, (intermediate)
3'-Trifluoromethylphenyl-2-carboxy-4-methylphenyl urea. M.p. 183-184 °C.
3'-Trifluoromethylphenyl-4-bromo-2-carboxyphenyl urea. M.p. 199-200 °C.
3'-Trifluoromethylphenyl-3-carbamoylphenyl urea. M.p. 205-206 °C.
3'-Trifluoromethylphenyl-3-sulfamoylphenyl urea. M.p. 184-185 °C.

3'-Trifluoromethylphenyl-5-chloro-2-phenylsulfonamidocarbonylphenyl urea.
M.p. 270-300 °C (dec.)

3'-Trifluoromethylphenyl-2-methylsulfonamidocarbonylphenyl urea.
3'-Trifluoromethylphenyl-6-methyl-2-carboxyphenyl urea. M.p. 166 °C.
3'-Trifluoromethylphenyl-3-methyl-2-carboxyphenyl urea. M.p. 181-182 °C.
3'-Trifluoromethylphenyl-4-hydroxy-2-carboxyphenyl urea. M.p. 166-167 °C.
4'-Nitrophenyl-2-carboxyphenyl urea. M.p. 203-204 °C.
3'-Trifluoromethylphenyl-2-carboxymethylphenyl urea. M.p. 182-1 83°C.
3'-Trifluoromethylphenyl-2-sulfophenyl urea. M.p. 182-183°C.
3'-Trifluoromethylphenyl-2-carboxyphenyl thiourea. M.p. 210-220°C.
3'-Trifluoromethylphenyl-2-carboxy-5-trifluoromethylphenyl urea. M.p. 179 °C.
3'-Trifluoromethylphenyl-4,5-dimethoxy-2-carboxyphenyl urea. M.p. 198-199 °C.
3'-carboxyphenyl-2-hydroxy-5-chlorophenyl urea. M.p. 216 °C.
3'-carbamoylphenyl-2-hydroxy-5-chlorophenyl urea. M.p. 203-204°C.
3'-Trifluoromethylphenyi-2-hydroxy-4-nitro-5-carboxyphenyl urea. M.p. 201-203 °C.

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Example 2

(intermediate)

2-Chloro-5-hydroxybenzoic acid

5-Amino-2-chlorobenzoic acid (85%, 10g, 49.7 mmol) was suspended in diluted
sulphuric acid (1 .25%, 800 mL) and cooled to 5 °C on an ice bath. Sodium nitrite (5g,
72 mmol) dissolved in water (150 mL) was added slowly while keeping the temperature
of the reaction below 5 °C. After addition of the sodium nitrite the reaction was stirred
for another 45 min at 5-10 °C until a clear solution was obtained. The reaction mixture
was poured into hot (70-85 °C) water (1 .5 L), charcoal added and the reaction mixture
heated at reflux for 25 min. Filtration and extraction with ethyl acetate afforded 6.7g of
the desired product as light brown crystals

Example 3

(intermediate)

2-Chloro-3-hydroxy-4-nitro-benzoic acid

To a solution of 2-chloro-5-hydroxybenzoic acid (6.5g, 38 mmol) in cold acetic acid
(150 mL) was added concentrated nitric acid (2.7 mL, 38 mmol). After addition the
reaction mixture was stirred for 30 min at room temperature then heated at 35 °C for
20 min. The reaction mixture was poured into ice and the product filtered off to give 1 .5
g of the desired compound as yellow crystals.

Example 4

(intermediate)

4-Amino-6-chloro-3-hydroxybenzoic acid

2-Chloro-3-hydroxy-4-nitro-benzoic acid (2.2g, 10 mmol) dissolved in ethanol (120 mL)
was reduced over Raney-Ni to give 1 .7 g of black crystals.

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Example 5

3-Trifluoromethylphenyl-4-carboxy-5-chloro-2-hydroxyphenyl urea

4-Amino-6-chloro-3-hydroxybenzoic acid (1.6g, 8.6 mmol) and 3-tifluoromethylphenyl
isocyanate (1.2 ml_, 9 mmol) were mixed in toluene (100 ml_). The reaction was heated
at reflux for 2 hr. The cooled reaction was filtered. The crude product was dissolved in
ethanol at reflux and treated with activated charcoal. Subsequent re-crystallisation
from ethyl acetate afforded the 1.2 g of the desired compound. M.p. 267-268 °C.

Example 6

3'-Trifluoromethylphenyl-2-amino-5-chlorophenyl urea

3-Trifluoromethylphenyl-5-chloro-2-nitrophenyl urea (4.0g, 11 mmol) was dissolved in
ethanol (200 mL). Raney-Ni (approx. 2 g) was added and the reaction hydrogenated
for 4 hr at room temperature. Filtration and evaporation of the solvent afforded 3.2g of
the desired compound as light pink crystals.

Example 7

3 -Trifluoromethylphenyl-5-chloro -2-methanesulfonylaminophenyl urea

3'-Trifluoromethylphenyl-2-amino-5-chlorophenyl urea (0.5g, 1 .5 mmol),
methanesulphonylchloride (1 .19 mL, 2.5 mmol), pyridine (0.4 mL, 5 mmol) and
tetrahydrofuran (25 m) were mixed and heated at reflux for 5 hr. The reaction mixture
was poured into water and extracted with ethyl acetate. The crude product was purified
by column chromatography on silica gel using toluene/ethyl acetate (1:1) as eluent. 0.1
g of the desired material was obtained. M.p. 185-186 °C.

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PCT/EP97/02723

Example 8

3'-Trifluoromethylphenyl-2-carboxyphenyl urea isopropyi ester

To 3'-trifluoromethylphenyl-2-carboxyphenyl urea (3.24 g, 10 mmol) was added thionyl
chloride (15 mL). After heating the reaction at 50 °C for 1 hr the excess thionyl chloride
was evaporated. The residue was stirred up in diethyl ether and filtered off to give 2.9
g of the desired acid chloride. The acid chloride (1 .5 g) was added to isopropanol (15
mL). The reaction was stirred at room temperature overnight. The solvent was
evaporated and the residue re-crystallised from ethanol (96%, 20 mL) to give 0.65 g of
the desired material. M.p. 137-138 °C.

Analogously were made:

3'-Trifluoromethylphenyl-2-carboxyphenyl urea methyl ester. M.p. 169-170 °C.
3'-Trifluoromethylphenyl-2-hydrazinocarbonylphenyl urea. M.p. 172-173 °C.
3'-Trifluoromethylphenyl-2-hydroxylaminocarbonylphenyl urea. M.p. 210-212 °C.

Example 9

2-<3'-Trifluoromethylbenzylcarboxamido)benzoic acid

To 3-trifluoromethylphenylacetic acid (2.70 g, 13.2 mmol) in diethyl ether (100 mL) was
added thionyl chloride (2 mL, 27 mmol). After heating at reflux for 1 hr the reaction
mixture was evaporated to dryness. The residue was dissolved in diethyl ether and 2-
aminobenzoic acid (1 .85 g, 13.5 mmol) was added followed by triethylamine (5 mL).
After stirring for 30 min water was added and the organic phase washed with 4 N
hydrochloric acid. Re-crystallisation from aqueous ethanol gave 0.95 of the desired
material. M.p. 162-164 °C.

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Example 10

(intermediate)

2-methylsulfonamidocarbonylaniline

Lithium methanesulfonamidate (1.0 g, 10 mmol) and isatoic anhydride (1.63 g, (10
mmol) in dimethyl sulfoxide (5 mL) were heated at 80 °C for 30 min. The reaction was
cooled down to room temperature and acidified with hydrogen chloride in diethyl ether.
The ether was evaporated and water added. The precipitated oil was purified by
column chromatography on silica gel eluting with ethyl acetate/methanol (95:5). The
desired material was obtained in a yield of 0.52 g.

Analogously were made;
2-phenylsulfonamidocarbonylaniline

Example 1 1

3'-Trifluoromethylphenyl-4-carboxyphenyl urea

3'-Triflouromethylphenyl isocyanate (1 .7 mL, 10 mmol) and 4-aminobenzoic acid (1 .37
g, 10 mmol) were stirred in dimethyl sulfoxide (20 mL) for 30 min. The reaction mixture
was poured into water. The precipitate was filtered off and washed with water. The
filter cake was stirred up in 4 N sodium hydroxide and filtered through celite. The
filtrate was acidified and the precipitate filtered off. Washing with water and drying in
the air afforded 3.0 g of the desired material. M.p. >300 °C.

Analogously were made:

3'-Trifluoromethylphenyl-2-carboxy-4-nitrophenyl urea. M.p. 185-186 °C.
3'-Trifluoromethylphenyl-2-carboxynapht-3-yl urea. M.p. 197-198 °C.
3'-Trifluoromethylphenyl-4-methoxy-2-carboxyphenyl urea. M.p. 175-176 °C.
3'-Methoxyphenyl-2-carboxyphenyl urea. M.p. 162-163 °C (dec).
4'-Bromophenyl-2-carboxyphenyl urea. M.p. 153-154 °C (dec).

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PCT/EP97/02723

3'-Nitrophenyl-2-carboxyphenyl urea. M.p. 190-191 °C (dec).
2'-Methoxyphenyl-2-carboxyphenyl urea. M.p. 160-161 °C (dec).
4'-Methoxyphenyl-2-carboxyphenyl urea. M.p. 175-176 °C (dec).
1 '-Naphthyl-2-carboxyphenyl urea.

2'-Trifluoromethylhenyl-2-carboxyphenyl urea. M.p. 172-163 °C (dec).
4'-Methylphenylsulfonyl-2-carboxyphenyl urea. M.p. 166-168 °C (dec).

Example 1 2

(intermediate)

Ethyl N-(2-bromoethyl)aminobenzoate

Dibromomethane (21.5 mL, 0.25 mol), ethyl-2-aminobenzoate (3.7 mL, 0.25 mmol)
and triethylamine (4.2 mL, 30 mmol) were mixed in dimethylformamide (50 mL) and
heated at 1 10°C for five hours. After cooling to room temperature the reaction was
poured onto ice and extracted with diethyl ether. The organic solution was washed with
water, dried over magnesium sulphate and evaporated to dryness. The residue was
purified by column chromatography on silica gel using dichloromethane as eluent to
give 3.3 g of the desired material.

Example 13

N'-(3-Trifluoromethylphenyl)-N-(2-ethyloxycarbonylphenyl)-1,2-diaminoetriane

Ethyl N-(2-bromoethyl)aminobenzoate (3.3 g, 12 mmol), 3-aminobenzotriflouride (1.5
mL, 12 mmol) and triethylamine (2 mL, 14 mmol) were mixed in dimethylformamide (25
mL). The reaction mixture was heated at 1 10°C for five hours. The cooled reaction
mixture was poured into water and extracted with diethyl ether. Purification by column
chromatography on silica gel using dichloromethane as eluent gave 1 .6 g of the
desired material.

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Example 14

N-(3-Trifluoromethyl)phenyl-N -(2-carboxy)phenylsulfamide

A mixture of 3-acetamidobenzotrifluoride (3.0 g, 15 mmol) and 60% sodium hydride
(0.6 g, 15 mmol) was stirred in toluene overnight at 60 °C. A solution of thionyl chloride
(1.2 mL, 15 mmol) in petroleum ether (10 ml_) was added to the mixture while keeping
the temperature below 8 °C. After stirring at 6-8 °C for 2 hr the reaction was filtered
and the filtrate evaporated to dryness. The residue was dissolved in diethyl ether (50
mL) and 2-aminobenzoic acid (2.0 g, 15 mmol) was added. After heating the reaction
at reflux for 1 3 hr the solvent was evaporated. The residue was heated to reflux in 2N
sodium hydroxide. The reaction was acidified and the precipitate filtered off.
Purification by column chromatography on silica gel using ethyl acetate as eluent gave
the desired compound. M.p. 162-163 °C.

Example 15

3'-Trifluoromethylbenzyl-2-carboxyphenyl urea

To a solution of di-tert-butyl dicarbonate (0.68 g, 3.13 mmol) in methylene chloride (25
mL) were added dimethylaminopyridine (36 mg, 0.3 mmol) and 3-
trifluoromethylbenzylamine (0.43 mL. 3 mmol). After stirring for 20 min at room
temperature 2-aminobenzoic acid (0.43 g, 3.13 mmol) was added. The reaction was
heated at reflux overnight. The solvent was evaporated and the residue dissolved in
ethyl acetate. The solution was washed with 1 M hydrochloric acid and water. The
solvent was evaporated and the residue suspended in water. 4 N Sodium hydroxide
(1.25 mL, 5 mmol) was added. The resulting suspension was washed with diethyl ether
and acidified with 4 N hydrochloric acid. The precipitate was filtered off and washed
with water. Re crystallisation from aqueous ethanol gave 80 mg of the desired
material. M.p. 176-178 °C.

The compound 3'-trifluoromethyl-4-phenylphenyl-2-carboxyphenyl urea, M.p. 191-192
°C (dec), was prepared analogously.

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Example 16

(intermediate)

2-Amino-4-phenylbenzonitrile

A mixture of 2-amino-5-bromobenzonitrile (1 .0 g, 5 mmol), phenylboronic acid (0.92 g,
7.5 mmol), tetrakis(triphenylphosphine)palladium (50 mg) and potassium carbonate
(3.5 g, 25 mmol) in dimethoxyethane/water 2:1 (60 mL) was heated at reflux for 4
hours. After cooling to room temperature the reaction was diluted with water and
extracted with ethyl acetate. The organic phase was dried and solvent evaporated.
Trituation with petroleum ether gave 0.89 g of the desired compound.

Example 1 7

2-(3'-Trifluoromethylphenyloxycarbonylamino)benzoic acid

To a solution of 1 .9 M phosgene in toluene (6.3 mL, 12 mmol) was added 3-
hydroxybenzotrifluoride (1.62 g, 10 mmol) in toluene (30 mL) followed by triethyl amine
(1.7 mL, 12 mmol) in toluene. After stirring for 15 min 2-aminobenzoic acid (1.37 g, 10
mmol) was added. >The reaction was stirred overnight at room temperature. The
precipitate was filtered off and washed successively with water, toluene and petroleum
ether to give 1.0 g of the title compound. M.p. 150-152 °C.

Example 18

3'-Trifluoromethylphenyl-5-chloro-2-aminophenyl urea

To a solution of 3'-trifluoromethylphenyl-5-chloro-2-nitrophenyl urea (1.0 g, 2.8 mmol)
in ethanol (50 mL) was added Raney-nickel. After stirring overnight the reaction was
filtered and the filtrate evaporated to dryness to give 0.8 g pink crystals. M.p. 308 °C.

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25

CLAIMS:

1.

A compound having the formula

R

X

Y

Z

or a pharmaceutical^ acceptable salt thereof
wherein

one of R 1 , R 2 and R 3 is a non-cyclic acidic group having a pKa value below 8 or
a group which is in vivo convertible to such a group;

R 4 , R 5 and the other two of the substituents R 1 , R e and R 3 are each independently
selected from hydrogen; alkyl; cycloalkyl; cycloalkylalkyl; alkenyl; alkynyl; alkoxy;
hydroxy; halogen; trifluoromethyl; trifluoromethoxy; cyano; nitro; amino; and aryl, aralkyl,
arylamino, aryloxy, aryl-CO-, or heteroaryl, wherein the aryl and heteroaryl groups may
be substituted one or more times with substituents selected from alkyl, cycloalkyl,
cycloalkylalkyl, alkenyl, alkynyl, hydroxy, alkoxy, halogen, trifluoromethyl,
trifluoromethoxy, cyano, nitro and amino; or R 3 and R 4 or R 4 and R 5 together form a
fused 4 to 7 membered carboxyclic ring which may be unsaturated, or partially or fully
saturated, while the other substituents R\ R 2 , R 3 , R 4 and R 5 is as defined above;

Y is -CO-, -CS-, -S0 2 -, or -C(=N-R 8 )-, wherein R 8 is hydrogen, alkyl, or cyano;

X is -NH-, -CH 2 -NH-, or -S0 2 -NH-;

Z is NR 6 , O, -CH=CH-, -C^C-, -N=CH-, or -CH=N-; wherein R 6 is hydrogen, or alkyl;

R 11 , R 12 , R 13 , R 14 and R 15 are each independently selected from hydrogen; alkyl;
cycloalkyl; cycloalkylalkyl; alkenyl; alkynyl; alkoxy; hydroxy; halogen; trifluoromethyl;
trifluoromethoxy; cyano; nitro; amino; -NHS0 2 -R 7 , -COOR 7 , -S0 2 N(R 7 ) 2 , -S0 2 OR 7 and

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PCT/EP97/02723

-CO-R 7 , wherein R 7 is hydrogen, alkyt, cycloalkyl, cycloalkylalkyl, alkenyl, alkynyl, aryl or
aralkyl; and aryl, aralkyl, arylamino, aryloxy, aryl-CO-, or heteroaryl, wherein the aryi and
heteroaryl groups may be substituted one or more times with substituents selected from
alkyl, cycloalkyl; cycloalkylalkyl; alkenyl; alkynyl; hydroxy, alkoxy, halogen,
trifluoromethyl, trifluoromethoxy, cyano, nitro and amino; or one of R 11 and R 12 , R 12 and
R 13 , R 13 and R u or R 14 and R 15 together form a fused 4 to 7 membered carboxyclic ring
which may be unsaturated, or partially or fully saturated, while the other substituents R 11 ,
R 12 , R 13 , R 14 and R 15 is as defined above.

2. A compound according to claim 1 wherein one of R 1 , R 2 and R 3 is NH 2l
-COOR 9 , -CH 2 COOR 9 , -CONH 2 , -NHS0 2 -R 9 , -S0 2 N(R 9 ) 2 , -S0 2 OR 9 , -P0 3 H 2 ,
-P0 3 RH, -P0 2 NH 2 , -CONHOH, -CONHCN, -CONH 2 S0 2 R 9 and -CONHNH 2 , wherein R 9
is hydrogen, alkyl, cycloalkyl, cycloalkylalkyl, alkenyl, alkynyl, aryl or aralkyl, and the
other of R 1 , R 2 and R 3 is as defined in claim 1 .

3. A pharmaceutical composition comprising a therapeutically effective amount of
a compound of claims 1 to 2 or a pharmaceutical ly acceptable salt thereof together
with at least one pharmaceutical^ acceptable carrier or diluent.

4. The use of a compound according to claims 1 to 2 for the preparation of a
medicament for the treatment of a disorder or disease of a living animal body,
including a human, which disorder or disease is responsive to the blockade of chloride
channels.

5. The use of a compound according to claims 1 to 2 for the preparation of a
medicament for the treatment of sickle-cell anaemia, brain oedema following
ischaemia, or tumours, diahreea, hypertension (diuretic), glaucoma, allergic or
inflammatory conditions and ulcers.

6. A method for the treatment of a disorder or disease of a living animal body,
including a human, which disorder or disease is responsive to the blockade of chloride
channels, comprising administering to a living animal body in need thereof a
therapeutically effective amount of a compound according to claim 1 .

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PCT/EP97/02723

7. A method for the treatment of a disorder or disease of a living animal body
which disorder or disease is sickle-cell anaemia, brain oedema following ischaemia, or
tumours, diahreea, hypertension (diuretic), glaucoma, allergic or inflammatory
conditions and ulcers comprising administering to such a living animal body, including
a human, in need thereof a therapeutically effective amount of a compound according
to claim 1 .

8. A method for the preparation of a compound of claim 1 , comprising:
a) reacting a compound having the formula

wherein W is O, or S and R 11 , R 12 , R 13 , R 14 and R 15 is as defined above, with a
compound having the formula

wherein R 1 , R 2 ,R 3 , R 4 , R 5 and R 6 is as defined above, or
b) reacting a compound having the formula

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PCT/EP97/02723

wherein X, Y, R 6 , R 11 , R 12 , R 13 , R 14 and R 15 is as defined above, with a compound
having the formula

wherein Hal is halogen and R 1 , R 2 , R 3 , R 4 and R 5 is as defined above,

whereafter the compound obtained is optionally converted to another compound of the
invention and/or a pharmaceutically acceptable salt thereof is formed using
conventional methods.

9. The use of blockers of chloride channels of erythrocytes for the treatment of
sickle cell anaemia.

INTERNATIONAL SEARCH REPORT

Intem<> A Application No

PCT/EP 97/Q2723

A. CLASSIFICATION OF SUBJECT MATTER

IPC 6 C07C275/42 C07C311/39 C07C311/51 C07C335/22 CG7C275/40
C07C311/08 C07C311/60 C07C271/58 A61K31/19 A61K31/17
A61K31/18

According to International Patent Classification (IPC) or to both national classification and IPC

B. FIFXDS SEARCHED

Minimum documentation searched (classification system followed by classification symbols)

IPC 6 C07C

Documentation searched other than minimum documentation to the extent that such documents arc included in the fields searched

Electronic data base consulted during the international search (name of data base and, where practical, search terms used)

C. DOCUMENTS CONSIDERED TO BE RELEVANT

Category "

Citation of document, with indication, where appropriate, of the relevant passages

Relevant to claim No.

X

WO 94 22807 A (NEUROSEARCH A/S, DEN.) 13
October 1994

see page 29, line 3, 11-12, 15-18, 20

see example 8; page 33, line 8, 13

see page 34, line 17, 19, 24, 30-31, page

35, line 1-2, 4-5

see claims 1,3,5,11

1-3,5,7,
8

X

DE 29 28 485 A (BAYER AG) 29 January 1981
see examples 4, 44, 57, 67, 69, 70, 72,
112, 114, 119-121, 131

1,2

X

US 4 468 380 A (O'DOHERTY GEORGE 0 P ET
AL) 28 August 1984
see examples 1-11

1,2

X

US 3 798 268 A (TWEIT R) 19 March 1974
see claims; examples

-/--

1,2,8

HI

Further documents are listed in the continuation of box C.

Patent family members are listed in annex.

* Special categories of cited documents :

'A" document defining the general state of the art which is not
considered to be of particular relevance

'E' earlier document but published on or after the international
filing date

'L* document which may throw doubts on priority claim(s) or
which is cited to establish the publication date of another
citation or other special reason (as specified)

"O" document referring to an oral disclosure, use, exhibition or
other means

*P" document published prior to the international filing date but
later than the priority date claimed

T" later document published after the international filing date
or priority date and not in conflict with the application but
cited to understand the principle or theory underlying the
invention

"X* document of particular relevance; the claimed invention
cannot be considered novel or cannot be considered to
involve an inventive step when the document is taken alone

"Y" document of particular relevance; the claimed invention

cannot be considered to involve an inventive step when the
document is combined with one or more other such docu-
ments, such combination being obvious to a person skilled
in the art.

'&.' document member of the same patent family

Date of the actual completion of the international search

22 August 1997

Date of mailing of the international search report

2 9. 08. 97

Name and mailing address of the ISA

European Patent Office, P.B. 5818 Patentlaan 2
NL - 2280 HV Rijswijk
Tel. ( + 31-70) 340-2040, Tx. 31 651 epo nl.
Fax ( + 31-70) 340-3016

Authorized officer

Seufert, G

Form PCT/ISA,'2I0 (second iheec) (July 1992)

page 1 of 3

INTERNATIONAL SEARCH REPORT

C(Contitiuation) DOCUMENTS CONSIDERED TO BE RELEVANT

Interna A Application No

PCT/EP 97/02723

Category

Citation of document, with indication, where appropriate, of the relevant passages

Relevant to claim No.

US 3 784 564 A (ROHR W ET AL) 8 January
1974

see column 3, line 3 - line 13

GB 1 139 343 A (AGRIPAT ) 8 January 1969
see table I, examples 13-15, 17, 19, 43,
44

see table III, examples 26, 30-34
see claims 1,11,35

GB 828 231 A (J. R. GEIGY AG) 17 February
1960 '
see claims; examples

US 2 722 544 A (H. M. FEUERTHALEN) 1

November 1955

see claims; examples

GB 1 055 786 A (IMPERIAL CHEMICAL
INDUSTRIES) 18 January 1967
see claims; examples

JOURNAL OF MEDICINAL CHEMISTRY,
vol. 36, no. 22, 1993, WASHINGTON US,
pages 3397-3408, XP002038034
R. W. CARLING ET AL. :

"3-Nitro-3,4-dihydro-2(lH)-quinolones.
Exitatory amino acid antagonists acting at
glycine-site NMDA and

(RS) -alpha-ami no-3-hydroxy-5-methyl -4-isox

azolepropionic acid receptors"

see intermediate 37 for compound 17, table

see page 3407, left-hand column, line 17 -
line 21

JOURNAL OF ORGANIC CHEMISTRY,

1953, EAST0N US,
pages 1427-39, XP002038035
R. P. STAIGER ET AL. : "Isatoic anhydride.
III. Reactions with primary and secondary
amines"

see page 1427, formula III; page 1433,

table IV, example 10;

see page 1437, line 35 - line 50

DATABASE CROSSFIRE

Bei lsteininformationssysteme GmbH

XP002038037

see abstract

& J. PRAKT. CHEM. ,

vol. 2, no. 69, 1904,

page 33

K0ENIG:

1,2

1-3,8

1,2,8

1,2,8

1,2,8

1,2

1,2

1,2

Form PCT/ISA/2I0 (continuation of second sheet) (July 1992)

page 2 of 3

INTERNATIONAL SEARCH REPORT

Intemi il Application No

PCT/EP 97/02723

C.(ContinuaQon) DOCUMENTS CONSIDERED TO BE RELEVANT

Category * Citation of document, with indication, where appropriate, of the relevant passages

DATABASE CROSSFIRE

Bei 1 stein informationssysteme GmbH

XP002038038

see abstract

& CAN. J. RES. SECT. B,

vol. 23, 1945,

page 139, 155

LEITCH ET AL. :

DATABASE CROSSFIRE

Bei 1 stein informationssysteme GmbH

XP002038039

see abstract

& EGYPT. J. CHEM.,

vol. 20, 1977,

page 259, 265, 266, 275

FAHMY ET AL. :

CHEMICAL ABSTRACTS, vol. 107, no. 11,
14 September 1987
Columbus, Ohio, US;
abstract no. 89293,

WANG EM ANN , P. ET AL: "Chloride - channel
blockers in the thick ascending limb of
the loop of Henle. Structure-activity
relationship"
XP002038036

cited in the application
see abstract

& PFLUEGERS ARCH. (1986), 407 (SUPPL. 2),
S128-S141,

US 4 994 493 A (GREGER RAINER
February 1991
cited in the application
see claims

ET AL) 19

WO 96 08242 A (CHI LDRENS MEDICAL CENTER)
21 March 1996
see claims

Relevant to claim No.

1,2

1,2

4,6

5,7

5,7

. 1

Form PCT/ISA'210 (continuation of second jheelj {July 1992)

page 3 of

3

INTERNATIONAL SEARCH REPORT

In Clonal application No.

PCT/EP 97/02723

Box I Observations where certain claims were found unsearchable (Continuation of item I of first sheet

This (nlernauonai Search Report has not been established in respect of certain claims under Article 17(2)(a) for the following reasons:
1. | [ Claims Nos.:

because they relate to subject matter not required to be searched by this Authority, namely:

Remark: Although claims 6 and 7

are directed to a method of treatment of the human/animal
body, the search has been carried out and based on the alleged
effects of the compound/composition.

Claims Nos.:

because they relate to parts of the Internauonal Applicauon that do not comply with the prescribed requirements to such
an extent that no meaningful Internauonal Search can be carried out, specifically:

see next sheet

j | Claims Nos.:

because they are dependent claims and are not drafted in accordance with the second and third sentences of Rule 6.4(a).

Box II Observations where unity of invention is lacking (Continuation of item 2 of first sheet)

This International Searching Authority found multiple inventions in this international applicauon, as follows:

1 • I As a " squired additional search fees were umely paid by the applicant, this International Search Report covers all
1 1 searchable claims.

As all searchable claims could be searched without effort justifying an additional fee, this Authority did not invite payment
of any additional fee.

3- As only some of the required additional search fees were umely paid by the applicant, this Internauonal Search Report

1 1 covers only those claims for which fees were paid, specifically claims Nos.:

4 - CH No ret J uired additional search fees were Umely paid by the applicant. Consequently, this Internauonal Search Report is
restricted to the invention first mentioned in the claims; it is covered by claims Nos.:

Remark on Protest j j The additional search fees were accompanied by the applicant's protest

| | No protest accompanied the payment of additional search fees.

Form PCT/ISA/210 (continuation of first sheet (1)) (July 1992)

International Application No. PCT/EP 97/ 02723

FURTHER INFORMATION CONTINUED FROM PCT/ISA/210

The vast number of theoretically conceivable compounds resulting from the com-
bination of all claimed substituents precludes a comprehensive search for all com-
pounds according to claim 1 . For economic reasons the search has been limited to
compounds where at least one of the substituents R1 1-15 is a CF3-group.

Despite the above limitation the search revealed too many relevant documents
and/or compounds, so that the search report shall not be considered complete. The
citations in the search report are only a arbitrary selection of novelty destroying
compounds/documents.

INTERNATIONAL SEARCH REPORT

Information on patent family members

Interna A Application No

PCT/EP 97/02723

Patent document
cited in search report

WO 9422807 A

DE 2928485 A

US 4468380 A

US 3798268 A

US 3784564 A

GB 828231 A
US 2722544 A
GB 1055786 A

US 4994493 A

Publication
date

13-10-94

29-01-81

28-08-84

19-03-74

08-01-74

01-11-55

Patent family
member(s)

19-02-91

AU
CA
EP
FI
JP
NO

6537894 A
2160128 A
0693053 A

954746 A
8510448

953956

T
A

AU 544252 B
AU 6019480 A
EP 0022958 A
EP 0049538 A
JP 56016411 A
US 4405644 A

US
CA

4526997 A
1171782 A

NONE

NONE

NONE
NONE

NL 6407857 A
NL 6515458 A

DE 3527409 A

DE 3528048 A

DE 3682136 A

EP 0210574 A

Publication
date

24-10-94
13-10-94
24-01-96
17-11-95
05-11-96
07-12-95

23-05-85
15-01-81
28-01-81
14-04-82
17-02-81
20-09-83

02-07-85
31-07-84

GB 1139343 A CH

459977

A

CH

477172

A

31-08-69

DE

1568012

A

05-02-70

FR

1493102

A

23-11-67

NL

6606753

A

21-11-66

US

3609177

A

28-09-71

US

3676561

A

11-07-72

13-01-65
31-05-66

12-02-87
05-02-87
28-11-91
04-02-87

Form PCT/IS/V210 (patent family annex) (July 1992)

page 1 of 2

INTERNATIONAL SEARCH REPORT

Information on patent family members

Interna J Application No

PCT/EP 97/02723

Patent document

Publication

Patent family

Publication

cited in search report

date

member(s)

date

US 4994493 A

JP 62G29560 A

07-02-87

WO 9608242 A 21-03-96 AU 3634795 A 29-03-96

EP 0781128 A 02-07-97

Form PCT'ISA/210 (piUnt family annex) (July 1992)

page 2 of 2